An aneurysm is a dilation of a blood vessel that poses a risk to health from the potential for rupture, clotting, or dissecting. Rupture of an aneurysm in the brain causes stroke, and rupture of an aneurysm in the abdomen causes shock. Cerebral aneurysms are usually detected in patients as the result of a seizure or hemorrhage and can result in significant morbidity or mortality.
There are a variety of materials and devices which have been used for treatment of aneurysms, including platinum and stainless steel microcoils, polyvinyl alcohol sponges (Ivalone), and other mechanical devices. For example, vaso-occlusion devices are surgical implements or implants that are placed within the vasculature of the human body, typically via a catheter, either to block the flow of blood through a vessel making up that portion of the vasculature through the formation of an embolus or to form such an embolus within an aneurysm stemming from the vessel. One widely used vaso-occlusive device is a helical wire coil having windings that may be dimensioned to engage the walls of the vessels. (See, e.g., U.S. Pat. No. 4,994,069 to Ritchart et al.).
Coil devices including polymer coatings or attached polymeric filaments have also been described. See, e.g., U.S. Pat. Nos. 5,226,911; 5,935,145; 6,033,423; 6,280,457; 6,287,318; and 6,299,627. For instance, U.S. Pat. No. 6,280,457 describes wire vaso-occlusive coils having single or multi-filament polymer coatings. U.S. Pat. Nos. 6,287,318 and 5,935,145 describe metallic vaso-occlusive devices having a braided polymeric component attached thereto. U.S. Pat. No. 5,382,259 describes braid structures covering a primary coil structure.
In addition, coil designs including stretch-resistant members that run through the lumen of the helical vaso-occlusive coil have also been described. See, e.g., U.S. Pat. Nos. 5,582,619; 5,833,705; 5,853,418; 6,004,338; 6,013,084; 6,179,857; and 6,193,728.
U.S. Pat. Nos. 6,620,152; 6,425,893; 5,976,131 5,354,295; and 5,122,136, all to Guglielmi et al., describe electrolytically detachable embolic devices. U.S. Pat. No. 6,623,493 describes vaso-occlusive member assembly with multiple detaching points. U.S. Pat. Nos. 6,589,236 and 6,409,721 describe assemblies containing an electrolytically severable joint.
However, none of these documents describe stretch-resistant vaso-occlusive devices as described herein, stretch-resistant vaso-occlusive devices that are flexible with respect to the detachment junction, or methods of making and using such devices.